Pressure fluid distributor valves



June 9 1959 J. MERCIER l 2,889,814 PRESSURE FLUID DISTRIBUTOR` VALVESoriginal Fileduan. 14, 1948 United States Patent C PRESSURE FLUIDDISTRIBUTOR VALVES Jean Mercier, New York, N.Y.

Original application January 14, 1948, Serial No. 2,286,

now Patent No. 2,787,255, dated April 2, 1957. Divided and thisapplication February 17, 1954, Serial No. 410,953

Claims priority, application Luxemburg January 22, 1947 3 Claims. (Cl.121-46.5)

This invention relates to pressure fluid distributor valves comprisingtwo coaxially aligned valves permitting a precise and undelayed openingand closing of ports or orifices controlled thereby and this is trueregardless of the fluid used or the circuit in which the distributor isinserted.

The present application is a division of application, Serial No. 2,286,tiled January 14, 1948, now Patent No. 2,787,255, issued April 2, 1957.

In known distributors of this kind, the two coaxial valves are mountedwithin a valve casing coaxially therewith, whereby the movable member ofone of the valves forms the seat for the movable member of the othervalve, the displacements of which are guided by an inner wall portion ofthe valve casing in such a manner that this other movable valve memberwill engage its `seat in a more or less well centered position. When thetwo valves are mounted within a valve casing so that their axialdisplacements are guided by the casing itself, it will be necessaryeither to produce precise machined guiding surfaces for maintaining thetwo valvesA always in coaxial relation, or to provide for a transverseplay permitting one of the valves to seat perfectly on the other valvewhen either one of the valves returns to its closed position; it isdilcult to determine in advance the exact amount of transverse playpermitting the valves to center themselves on the respective seat duringreturn movement into closed position since a too small play may beinsuicient whereas a too great play may cause undesirable leakage; thus,the provision of a predetermined transverse play may be considered as atrial and error method, that is, the chosen amount of transverse playmay be satisfactory in one case and unsatisfactory in another case.

The object of the present invention is to remedy these drawbacks and toprovide for precision alignment of the movable valve members regardlessof their transverse play or the machining of their guiding surfaces,thereby improving the structure of the distributor valve, facilitatingproduction and minimizing its cost of manufacture.

The distributor valve construction according to the present inventionwill now be described by way of example with reference to theaccompanying drawing which shows a iiuid pressure control systemembodying two distributor valves.

In the drawing there is vshown a hydraulic control system incorporatingtwo distributor Valves. The hydraulic control system comprises acontrolled element constituted by a hydraulic motor M and a controlelement constituted by a lever 40 pivoted at 41 to the body of a controldevice including two distributors D1 and D2. Distributor D1 comprises aninlet valve 42 and an outlet valve 43, and distributor D2 an inlet valve44 and an outlet valve 45. The inlet valve 42 of distributor D1 controlsthe communication between a lpressure liquid supply conduit 46 and aconduit 47 leading to the left side of motor M, whereas the inlet valve44 of distributor D2 controls the communication between said supplyconduit 46 and a conduit 48 leading to the right side of Fatented June9, 1959 motor M. The outlet valve 43 of distributor D1 controls thecommunication between the conduit 47 and a discharge or exhaust conduit49, and the outlet valve 45 of distributor D2 the communication betweenthe conduit 48 and said discharge conduit 49. The inlet valves 42 and 44are constantly urged towards their corresponding seats by spring members50 and 51, respectively, and the outlet valve 45 of distributor D2 ismaintained in abutting contact with the rod of a piston 52 mounted in acylindrical chamber formed in the body of distributor D2. The space 57of this cylindrical chamber at the right side of piston 52 may beconnected through ducts 53, 54 and 55 and distributor D1 either with thepressure liquid supply conduit 46 or with the discharge conduit 49. Aspring 56 is yarranged in the cylindrical chamber to urge piston 52constantly towards the outlet valve 45.

The operation of the control system can be easily understood:

When the lever 40 occupies the position shown in the drawing thepressure liquid supplied through the conduit 46 iiows through the openinlet valve 44 of distributor D2 and conduit 48 to the right side ofmotor M, while the `left side of this motor is connected, throughconduit 47 and the open outlet valve 43 of distributor D1, with thedischarge conduit 49. But when the upper end of lever 40 is displacedfrom left to right so as tot close the outlet valve 43 of distributor D1to therebyinterrupt the communication between the left side of motor' M1and the discharge conduit 49, the liquid coming from containing thepiston 52 so as to push the latter against the action of springl 56'toward the 'outer end of the cylindrical chamber. Spring 51 is thusallowed to. close the inlet valve 44 of distributor D2 so that the twodistributors of the control device are in neutral, i.e. closed position.When lever 40 is further actuated to open the inlet valve 42 ofdistributor D1 in order to connect the left side of motor M and thespace 57 of the auxiliary chamber of distributor D2 with the pressureliquid supply conduit 46, the piston 52 will be further displaced to theleft to allow the outlet valve 45 of distributor D2 to open under theaction of the pressure liquid coming from the right side of motor M sothat this liquid can discharge through conduit 49.

As it has been mentioned above, the improved distributor valvesaccording to the invention may be used with any pressure uid and anycircuit, but are particularly applicable to be used as pressure reducingvalves and in hydraulic transmission or control systems comprising aslave unit with a lfollow-up action to bring the movable member of theslave unit to a position corresponding exactly to that occupied by avalve actuating member, the distributor valves permitting not only toreproduce exactly the displacements of the movable part of thedistributor by the slave unit with an absolute precision and without anytime lag, but also to ensure at all times a perfect fluid-tight closingof the aligned valves due to their exact concentricity with respect toeach other.

What is claimed is:

1. A control device for a fluid motor, comprising, in combination, acasing formed with a first valve chamber and a second valve chamber,said rst valve chamber having an inlet port, an outlet port and atake-oil port communicating with one side of said iiuid motor, and saidsecond valve chamber having an inlet port communicating with the inletport of said rst valve chamber, an outlet port communicating with theoutlet port of said iirst valve chamber, and a take-ott portcommunicating with the other side of said Huid motor, a valve seatformed in each valve chamber between said inlet ports and said take-offports, respectively, a movable valve'member in each chamber cooperatingwith said valve seat thereof to constitute an inlet valve, an outletvalve in each chamber arranged in alignment with :the vcorrespondinginlet k'valve andfhaving a "closure member adapted 'to 'cooperate withAa seat formed'on 'the corresponding movable valve member, a passageineach inlet valve controlled by thecorr'esponding outlet valve, a boreformed 'in said casing 'in align ment with said iirst valve chamber, 'apistonfslidable in said bore and 4having its Working face formed 'withan aXial .projectionextending linto said rst valve chamber so as`to`contact the outlet valve therein, resilient means in said borearranged t'o urge said piston in a direction in'Which-said extensionopens said inlet valve inltheffirst valve chamber without moving theoutlet valve 'in said first -valve chamber ofits seat, a passageway insaid-casing for interconnecting the space of'said borein'fr'ont of saidworkingface ofthe piston with the talte-o port of said second valvechamber, -and valve actuating means adapted to open one of the valves insaid second valve chamber Withoutmoving the other valve of its seat,whereby said space in front of the working face of said piston will beconnected either with the inlet -port or with the outlet port of saidsecond valve chamber and the 'valves in said iirst valve chamberactuated through said piston so as tocontrol the operation of said Huidmotor in accordance with the control motion of said valve actuatingmeans.

2. A device as delined in claim l wherein said valve actuating meansincludes a bore in said casing in alignment with said second chamber, acylinder slidably mounted in said last-mentioned bore and having Varecess in one side thereof, said cylinder bearing vagainst the outletvalve in said second chamber, and a lever -ipivotally mounted in saidcasing and having its inner end engaged and a second valve chamber, eachvalve chamber having an inlet port means, an outlet port means and/atake-ott port means, iirst movable valve means arranged in said firstvalve chamber to selectively provide an inlet passage between said inletport means and said take-0E port means or an outlet passage ibetweensaid take-oi port means and said outlet port means of said irst valvechamber, resilient means in said casing to urge said viirst valve meansin one direction to close-said outlet passage and to open said inletpassage, second movable valve means arranged in said secondvalve'elia'mberto selectively .provide an inlet passage between the inletport means and the take-off port means or an outlet passage between thetake-01T port means and the outlet port means of said second valvechamber, uid pressure responsive means associated with said tirst valvemeans and communicating with the take-off port means of said secondvalve chamber to move said first valve means in the opposite directionagainst the'actionof said resilient means inresponse to iluid pressurein the :take-ott port means of said second valve chamber, to therebyclose the inlet 'passage and `open the outlet `passage in said rst'valve chamber, and valve actuating -means adapted to operate saidsecond valve means so as to open either the inlet passage for the outletpassagein said'second valve chamber.

References Cited in the file of this patent UNITED STATES PATENTS

